Real-World Assessment of Clinical Outcomes in Lower-Risk Myelofibrosis Patients Receiving Treatment with Ruxolitinib

• Published in: Blood 2014-12, Vol.124 (21), p.1857-1857
• Main Authors: Davis, Keith L, Kaye, James A., Cote, Isabelle, Gao, Haitao, Ronco, Julian Perez, Seifeldin, Raafat, Mendelson, Estella
• Format: Article
• Language: English
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood.V124.21.1857.1857

Introduction: Published trial data shows that ruxolitinib improves both splenomegaly-related and nonsplenomegaly-related constitutional symptoms in patients with intermediate-2 and high risk myelofibrosis (MF). However, few trial-based assessments of ruxolitinib in lower-risk MF patients have been conducted and no studies to date have made such assessments in a real-world population. In this study, we assessed changes in spleen size and constitutional symptoms during ruxolitinib treatment for lower-risk MF patients in real-world clinical settings. Methods: This was a retrospective, observational review of anonymized medical record data collected in January 2014 by 49 hematologists and oncologists in the United States. Patient inclusion criteria were: (1) diagnosed with lower-risk MF (International Prognostic Scoring System score of 0 or 1); (2) first treated with ruxolitinib ≥3 months before the medical record abstraction date; (3) ≥18 years of age at ruxolitinib initiation; (4) complete medical history from MF diagnosis until the medical record abstraction date; and (5) never enrolled in an MF-related interventional trial. Minimum quotas of n=50 and n=25 were set for intermediate-1 and low-risk patients, respectively, with a predetermined maximum of 110 patients in the combined total. Spleen size and constitutional symptoms were retrospectively observed at MF diagnosis, at ruxolitinib initiation, and at best response while on ruxolitinib. Spleen size was captured via predefined categories of no splenomegaly (spleen not palpable), very mild or mild splenomegaly (20 cm palpated). Symptoms of interest included those captured in the MPN Symptom Assessment Form (MPN-SAF), which were categorized as mild, moderate, or severe based on medical notes recorded at each time point. For this abstract, we present findings on the 7 most commonly observed MPN-SAF symptoms in our sample. This study was exploratory and used only descriptive analyses. Results: A total of 108 patients were included in the study (25 low-risk and 83 intermediate-1 patients). Ruxolitinib start dates spanned January 2012 – November 2013. All low-risk patients were ≤65 years of age, and nearly 80% of intermediate-1 patients were ≤65 years of age. The majority of patients in both risk groups (60% and 69%, respectively) were male. A higher proportion of intermediate-1 patients were positive for JAK2 V617F mutation